کالیفرنیا برکلی/پزشکی سانفرانسیسکو، برکلی و سانفرانسیسکو، آمریکا
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A combination of light microscopy and image processing was applied to investigate morphology of label-free primary-melanocytes and melanoma cells. A novel methodological approach based on morphology of nuclear body was used to find those single cells, which were at the same phase of cell cycle. The area and perimeter of melanocytes and melanoma cells were quantified. We found that there was a significant difference between area and perimeter of adendritic-shaped melanocytes with melanoma cells and the reason (s) of this finding was speculated. Finally, a theoretical model based on losing dendrites was proposed, which was in agreement with our experimental data.
ObjectiveMicro-nano scale surface modification of Ti-6Al-4V was investigated through the fascinated modern fiber engraving laser method. The process was performed at a high laser speed of 2000?mm/s, under different laser frequencies (20–160?kHz) and groove distances (0.5–50?μm).MethodsTopographic evaluations such as Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FE-SEM) were used to identify the quality and regularity of patterns. The proliferation of human osteoblast-like osteosarcoma cells (MG63) was analyzed by MTT assay for up to 72?h. Also, the plate counting method was used to quantify the viability potential of the modified surface against Escherichia coli bacteria.ResultsThe cellular viability of
Lung cancer is a leading cause of cancer death in both men and women worldwide. The high mortality rate in lung cancer is in part due to late-stage diagnostics as well as spread of cancer-cells to organs and tissues by metastasis. Automated lung cancer detection and its sub-types classification from cell’s images play a crucial role toward an early-stage cancer prognosis and more individualized therapy. The rapid development of machine learning techniques, especially deep learning algorithms, has attracted much interest in its application to medical image problems. In this study, to develop a reliable Computer-Aided Diagnosis (CAD) system for accurately distinguishing between cancer and healthy cells, we grew popular Non-Small Lung Cancer
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Organ-on-a-chip technology has gained great interest in recent years given its ability to control the spatio-temporal microenvironments of cells and tissues precisely. While physical parameters of the respective niche such as microchannel network sizes, geometric features, flow rates, and shear forces, as well as oxygen tension and concentration gradients, have been optimized for stem cell cultures, little has been done to improve cell-matrix interactions in microphysiological systems. Specifically, detailed research on the effect of matrix elasticity and extracellular matrix (ECM) nanotopography on stem cell differentiation are still in its infancy, an aspect that is known to alter a stem cell’s fate. Although a wide range of hydrogels s
Graphene quantum dots (GQDs) have attracted increasing attention due to their unique properties such as high water solubility, photoluminescence activity, good biocompatibility, physical, chemical and electrical properties which makes them appropriate candidates for use in a variety of bio-applications, sensors and photocatalysts. The objective of this study is synthesis of GQDs and improving their surface properties via chemical modification.Here, urea and citric acid as carbon precursor were used. Citric acid was self-assembled into graphene framework via hydrothermal method at 160 C for 4 h. Then, the synthesized GQDs were carbonized and chemically activated by KOH treatment. The surface area and pore structures of GQDs were analyzed by
A new method based on fluorescent probe of iron quantum cluster has been proposed for rapid detection of Escherichia coli (E. coli). The iron quantum cluster was synthesized using hemoglobin as both a source of iron and a protective agent (Hb-FeQCs). The investigation of the sensitivity of Hb-FeQCs towards metal ions showed a highly selective turn off fluorescence for Cu2+. It suggests that Cu2+ can induce fluorescence quenching by binding to amino acids of Hb. The ability of E. coli bacteria to capture and reduce of Cu ions caused to efficient recovery of the fluorescence of Hb-FeQCs from Cu2+-caused quenching. This probe has a satisfactorily linear range of 0.35–35 μM for Cu2+ under the optimal iron quantum cluster concentration (500
Template-mediated self-assembly synthesis has produced a diverse range of biomimetic materials with unique physicochemical properties. Here, we fabricated novel fluorescent three-dimensional (3-D) hydroxyapatite (HAP) nanorod-assembled microspheres using iron quantum cluster (FeQC) as a hybrid template, containing three organic components: hemoglobin chains, piperidine, and iron clusters. The material characterization indicated that the synthesized HAP possessed a uniform rod-like morphology, ordered 3-D architecture, high crystallinity, self-activated fluorescence, and remarkable photostability. Our study proposed that this FeQC template is a promising regulating agent to fabricate fluorescent self-assembled HAP microspheres with a control
A new approach has been developed to improve sensing performances of electrochemically grown Au nanostructures (AuNSs) based on the pre-seeding of the electrode. The pre-seeding modification is simply carried out by vacuum thermal deposition of 5 nm thin film of Au on the substrate followed by thermal annealing at 500 C. The electrochemical growth of AuNSs on the pre-seeded substrates leads to impressive electrochemical responses of the electrode owing to the seeding modification. The dependence of the morphology and the electrochemical properties of the AuNSs on various deposition potentials and times have been investigated. For the positive potentials, the pre-seeding leads to the growth of porous and hole-possess networks of AuNSs on the
Objective: Transforming growth factor beta/single mothers against decapentaplegic (TGFβ/SMAD) signaling pathway plays important roles in various biological processes. It acts as a tumor suppressor during the early stages of cancer progression. Discovering the regulators of this pathway provides important options for therapeutic strategies. Here, we searched for candidate microRNAs (miRNAs) that potentially target the critical components of the TGFβ signaling pathway.Materials and Methods: In the current experimental study, we first predicted miRNAs that target TGFβ components using a bioinformatics software. After that, quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect the expression of miR-587, TGFBR2, SMAD4,
The low membrane permeability of lipophilic drugs was resolved using liposomes as a solubilizing agent and the precise size control of them is a significant parameter in drug carrier technology. Here, we have established a microfluidic octanol-assisted liposome assembly method to produce a surfactant-assisted liposome which has merged by the cytoskeleton drug (Taxotere) encapsulation in a single process step, then a complete microfluidic cellular analysis was performed in trapping cell device with an optofluidic assay for quantifying drug permeability. The optimization of process variables resulted in the formation of liposomes with particle size 6.75?0.5 ?m and monodispersity 6.2%, representing encapsulation efficiency and loading capacity
Wnt/β-catenin signaling, a highly evolutionary conserved pathway, is abnormally regulated in many human cancers. This pathway is one of the proposed mechanisms of atrial natriuretic peptide (ANP) anti-cancer effect. ANP which at first reported as a cardio hormone, inhibits proliferation of different cancer cell lines and tumor growth in vitro and in vivo respectively. Previous studies have shown a possibility of direct interaction between ANP and Frizzled (FZD), the main extracellular receptor of the pathway, and so a competition between ANP and Wnt for binding to this receptor. Here, using a molecular dynamics approach, we investigated this hypothesis validity and also the probable mechanism involved. We found three overlapping binding re
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